Drilling mechanism



July 31, 1928.

E. G. GARTIN DRILLING MECHANISM Filed 00? 27, 1.924

' 4 in the usual manner. and the shell 4 are held in operative assem- Patented July 31, 1928.

Uhll l ldll STATES PATENT orrirs.

ELMER G. F GLABEMOET, NEW HAMPSHIRE, ASSIGNOR- TO SULLIVAN MACHTNERY COMPANY, A CORPORATION OF MASSACHUSETTS.

DRILLING MECHANISM.

Application filed October 27, 1924. Serial N0. 746,243.

My invention relates to drilling mechanisms.

I An object of my invention is to provide an improved drilling mechanism. Another object of my invention is to provide an improved drilling mechanism of the so-called drifter type wherein improved means are provided for guiding the utting end of the drill steel during the starting of the hole. Still another object of my invention is to provide an improved drilling mechanism having an improved centralizer for the drill steel. A still further object of my invention is to provide an improved drilling mechanism of the mounted manually fed type having improved means carried directly by the drill mounting for centralizing the drill steel to facilitate the starting of a hole. These and other objects and advantages of my invention will hereinafter more fully appear.

In the accompanying drawings I have shown for purposes of illustration one form which my invention may'assume in practice.

In these drawings,-- v

Fig. 1 is a side elevation of a drilling mechanism of the mounted type in which my improved drill steel guiding means is incorporated.

Fig. is a plan view of the forward end of the mechanism shown in Fig. 1.

Fig. 3 is transverse sectional view taken substantially on line 3-3 of Fig. 2, the guiding means for the drill steel being shown in a plurality of positions. I

Fig. 4 is a view similar to that shown in F ig. 3 showing the guiding means when used with a broaching steel.

In this illustrativeconstruction I have shown a drilling :nechanism generally designated 1 of the well known pressure fluid percussive type which is adapted to actuate a drill steel 2 provided with a cutting bit 3. The drilling mechanism 1 is slidably mounted in a stationary cradle or shell 4 provided with a base 5 which is adapted to be clamped to a column or tripod, not shown, in a well known manner. A feed screw 6 and a manual grasping handle 7 are provided for feeding the drilling mechanism 1 bodily back and forth relative to the cradle The feed screw 6 bled relation by means of parallelside rods 8.

In my improved construction it will be observed that a longitudinally extending arm or bracket 9 is provided having at its rear end spaced laterally extending apertured lugs 10 through which the side rods 8 of the cradle pass securing the member 9 rigidly to the forward end of the stationary cradle 4. The rear end of the arm 9 is provided with an upstanding boss 11 adapted to receive the forward end of the feed screw 6. The forward end of the arm 9 is disposed a substantial distance in front of the cradle 4 and is provided with an offset laterally extending portion 12 which has pivoted there to, as at 13, a clamp member 14. The portion 12 of the arm and the clamp member 14 are provided with concave surfaces 15 and 16 respectively within which semi-cylindrical flanged bushings 17 are secured as by screws 18 or any other usual fastening means. The concave surfaces of the memhere 17 are adapted to engage the cylindrical outer surface of the drill steel 2. The portion 12 of the arm 9 is provided with upstanding laterally spaced lugs 19 withwhich a lug 20 formed on the clamp l4is' adapted to cooperate and these lugs are provided with apertures 21 and 22'through which a locking pin 23 is adapted to pass. The pin 23 is held in position by a suitable cotter pin 24. It will also be observed that the portion 12 0f the arm 9 is provided with angularly disposed guiding surfaces 25 with which a plane guiding surface 26 formed on the pivoted clamp 14 cooperates, forming a rectagular opening which is adapted to receive a rectangular broaching steel 27, the bushings 17 being removed at this time (see Fig. 4). It will be clear that if it is not desired to remove the bushings 17 to permit using a breaching tool; said bushings may be terminated adjacent the lower and upper guiding surfaces 25 and 26.

In the operation of my improved drill steel guidingmeans it will be observed that after the drill steel 2 hasbeen inserted within the forward end of the drilling mechanism 1, the clamp 14 is swung from the dotted line position shown in Fig. 3 into the full line position shown in that figure, consequently causing the inner surfaces of the bushings 17 to engage the exterior surface of the drill steel 2. The clamping member 14 is disposed adjacentthe drill. bit 3 at this time. The motor of the drilling mechanism 1 is then started and the drill steel 2 percussively actuated, the drilling mechanism 1 being fed forwardly by means of the feed screw 6 as the hole deepens. As the hole is started the bushings 17 carried within the forward end of the arm 9 hold the drill steel in a centralized position. If a broaching steel is to be used the bushings 17 are removed and the steel 27 is guided by the surfaces 25 and 26 as shown in Fig. 4.

As a result of my improvement it will herein be noted that I have provided adrill ing mechanism having improved guiding means for a cylindrical or rectangular drill steel during the starting of the hole and in which the guiding means is carried directly by the stationary mounting for the drill.

It will further be noted that the guiding means is of exceedingly simple structure applicable to drilling mechanisms of standard forms with a minimum of change and expense. It will also be noted that my improved means for guiding either a broaching tool or drill steel includes an opening common to both.

Jhile I have in this application specifically described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a drilling mechanism, the combination with a support on Which the drill is longitudinally movable, said support includ ing side rods to hold the parts thereof in operative assembled relation, and a drill steel carried by the drill, of guiding means for the drill steel including an elongated supporting arm secured to the forward end of said supportby said side rods out of the path of movement of the drill whereby the forward end of the latter may be moved a substantial distance in advance of said support.

2. In. a drilling mechanism, the combination with a support on which the drill is longitudinally movable, said support including side rods to hold the parts thereof in operative assembled relation, of guiding means for the drill steel including an. elongated supporting arm secured to the forward end of said support by said side rods out of the path of movement of the drill whereby the forward end of the latter may be moved a substantial distance in advance of said support, and a steel engaging clamp carried by the forward end of said arm.

3. In a drilling mechanism, the combination with a support on which the drill is longitudinally movable, of guiding means for drill steels including a longitudinally extending supporting arm secured to said support, a bushing secured thereto, a member removably connected to the forward end of said arm, and a removable bushing carried by said member, said bushings adapted to receive and guide a drill steel of a certain cross section, said arm and said member cooperating in presenting a recess adapted to receive and guide a tool of differently shaped cross section.

in a drilling mechanism, the combination of a support on which the drill is longi-- tudinally movable, of guiding means for drill steels including a forwardly extending arm secured to said. support out of the path of movement of the drill, a clamping member pivotally mounted on said arm, and semi-cylindrical bushings secured to said arm and pivoted member respectively for receiving and guiding a drill steel of cylindrical cross section, said arm and pivoted member being also provided with means for selectively receiving and guiding a tool of another cross section.

In a drilling mechanism, the combination with a support on which the drill is longitudinally movable, of guiding means for drill steels including a longitudinally e2;- tending supporting arm, and means carried on the end of said arm for embracing a steel, said latter means being provided with a rectangular aperture and a cylindrical aperture intersecting the same to provide means for selectively guiding drill steels of differently shaped cross section.

In a drilling mechanism, the combination with a support on which the drill is longitudinally movable, of guiding means for drill steels including a longitudinally extending supporting arm, and means carried on the end of said arm for embracing a steel, said latter means being provided with a rectangular aperture and a cylindrical aperture intersecting the same to provide means for selectively guiding drill steels of differently shaped cross section, and removable means carried by said embracing means to provide a support for a cylindrical steel around substantially the entire periphery thereof.

In testimony whereof I aifiX my signature.

ELMER G. GARTIN. 

